Endoscopic techniques are routinely performed in small animal specialty practice for diagnosis and treatment of gastrointestinal, respiratory and urogenital disorders. Because these procedures are minimally invasive and cause little discomfort or complication for the clinical patient, their popularity and use in private practice has been increasing dramatically. Hundreds of veterinarians take continuing education workshops and purchase scope related equipment each year. Advanced training in the use of specialized equipment is necessary for use of this equipment. Additionally, significant practice is necessary to gain the dexterity and skill to successfully perform the procedures in a timely manner in clinical cases. In human medicine, endoscopists must demonstrate successful completion of a procedure using a simulator over 60 times before they are allowed to perform the procedure on a live human. Additionally, if they do not maintain a minimum caseload in the procedure, they may be required to re-train in order to renew their procedural certifications.
Veterinary training in the use and function of flexible and rigid endoscopes is currently often provided in the form of multiple day training workshops using live animals. In spite of the intensive focus, participants generally perform each procedure no more than twice. After completion of the workshops, practitioners return to their clinics where they employ their newly acquired skills on privately owned animals. Unless they obtain permission to practice on patients freshly euthanized for other reasons, they rarely have the opportunity to hone their skills further outside of actual clinical practice.
The animals used in teaching laboratories are generally terminated at the conclusion of the workshops because of the strain of prolonged anesthesia, damage sustained during training due to the initially steep learning curve for participants, and the number of participants performing each procedure on any given animal. Attempts to replace live animals with simulations for veterinary training have been hindered by technical difficulties in accurately replicating the live animal experience and ethical challenges.
Another difficulty is the necessity of having to clean or dispose of endoscopic devices after use with a cadaver or other living or once living tissue. For example, there are a variety of endoscopic devices for knot tying, grasping, cutting, or for performing other procedures that are not designed to be used on more than one patient, i.e., they are disposable. Because they cannot be cleaned, once they are used for a practice session on or within real tissue(s), their proper disposal is required. Many of these instruments are quite costly and using a new one for each training session can be expensive.
Unfortunately, there are a remarkable number of technical challenges in creating an animal surrogate for scoping. For example, the gastrointestinal tract is essentially a hollow and non-rigid tube that exists in a collapsed state except when filled with ingesta or fluid. It must be adequately insufflated with air to allow visualization of the internal surfaces of the esophagus, stomach, and intestine. Insufflation cannot be achieved in the gastrointestinal tract of cadavers because normal GI motility (muscular tone) is necessary to maintain closure of various sphincters and retain the insufflated air. As a result, the gastrointestinal tract remains collapsed and structures cannot be visualized. Unless procedures are performed immediately after euthanasia, cadavers must be stored frozen and then thawed for use. Inadequate thawing yields an immovable specimen with very poor tissue manipulation ability. Excessive thawing yields a specimen that has begun bloating with gas as it degrades; this also limits tissue manipulation. Most commonly, specimens will thaw patchily and be unsuitable for use. Finally, the availability of sufficient animal cadavers for use in a continuing education course is unreliable and may create incentive for potential suppliers of cadavers to prematurely euthanize adoptable animals.
Plastination of tissue specimens, wherein water and fats are removed from tissues and replaced with polymers, to create scope trainers has also been investigated. However, the significant friction of plastinated tissues can easily damage the outer sheath of flexible endoscopes, especially when the scopes are in the hands of novices. The lack of tissue pliability also creates significant torque on rigid endoscopes that can fracture the telescope lenses. In addition, the rigidity of such tissues prevents a true-to-life experience in the intricate and proper manipulation of the endoscope. Rather, the experience is more like pushing the endoscope through a rigid pipe. Hand-eye coordination and manipulative skills are not necessary to successfully navigate these surrogate GI tracts. The same tissue rigidity may prevent entry into the plastinated urinary tract entirely. Plastinated samples can be prepared after removal from cadaver animals and are scoped ex vivo, so the operator gains no appreciation for manipulation of the actual animal.
Although a variety of commercial simulators are available for training doctors and other medical professionals in different scoping procedures, they are cost prohibitive for veterinary training. The majority of human flexible scope trainers utilize computer simulation or virtual reality models of the gastrointestinal tract after the scope is inserted into the orifice of a rigid human facsimile. Such flexible endoscopy simulators often cost in excess of $100,000 per unit depending upon which simulations are chosen. Rigid scope trainers can be less expensive, but cost can still render them inaccessible for a veterinary educator.
There are other disadvantages for most of the commercial simulators currently being used. Most notable is their usual lack of transportability. Further, since most of them utilize computer simulations and/or force-feedback data, they usually require a dedicated computer system and related software which contribute not only to their cost but also to difficulty in transporting them.
Further, generally regarded as safe (GRAS) lubricants are often utilized during endoscopic procedures to facilitate movement of the instrument and aid in the comfort of the patient. The use of such lubricants must be judicious so as to not interfere with the endoscope images. With most computer simulated or virtual reality simulators, the use of lubricants is not possible because they are not usually designed to be cleaned. Thus, doctors and medical professionals that utilize such training devices will not gain experience in the use of lubricants during a procedure.
For veterinary continuing education purposes, at least six of any flexible or rigid training unit would be necessary. The high cost of most commercial trainers makes them financially inaccessible for veterinary colleges and certainly not an option for practitioners that wish to obtain ongoing practice in techniques they have acquired at workshops.